Process for the direct reduction of ores, and particularly of iron ores



Patented Apr. 21, 1925.

UNITED STATES PA'TE'NT- OFFICE.

"LUCIEN' PAUL BASSET, OF PARIS, FRANCE.

Io Drawing.

To all whom it may mm:

vBe it known that I, LUoIEN PAUL BAssE'r, of 54 Avenue Marceau, Paris, France, chemist engineer, have invented Processes for the Direct Reduction of Ores, and Particularly of Iron Ores, of which the following is a full, clear, and exact description.

In my prior United States, Patents Nos. 1,360,711 and 1,372,392, and in my pending United States application filed on the March 10th, 1920, under Serial No. 364,704, there ,are described various processes for the di rect production of iron and its alloys based upon the following principle:

The oreto be reduced is mixed with the necessary quantity of coal for effecting the reduction and the whole is heated by means of a flame obtained by the combustion of finely pulverized coal in the quantity of superheated air necessary for causing this combustion to practically give only carbon monoxide.

Under the action of this extremely hot flame the reaction of the coal on the ore is complete since no reverse reaction can take place, and the metal melts without any possible prejudicious reaction since the flame, and consequently the atmosphere of the furnace does not contain any element capable of yielding oxygen. Owing to this fact, the reduction of the slag of the furnace iron oxide. ,7

The accessory reactions of iron metallurgy in particular also are satisfactory due to these chemical conditions: by the process above set forth, sulphur, for instance, is extracted from the iron as a calcareous slag, since this process prohibits any oxidation of sulphide of calcium and consequently its reincorporation in the metal.

Experience has shown the applicant that the process which has just been mentioned is practically free of it mlght sometimes be advantageous 'as'far' as economy is concerned, to xuse a. heating flame contal-mng a certain PI'OPOItlOD of carbonic acid but always less than the pro economical than that of a flame ore is complete and the 392, 1,435,686 and in my PRQCESS TOR THE DIlCREOT REDUCTION OF ORES, AND PARTICULARLY OF IRON ORES, Application filed February 21, 1923. Serial No. 620,505.

ractically containing only carbon monoxi e for the two following reasons: 1. It is no longer necessary to crush the fuel so finely and the quantity of pulverized coal used can be reduced, thereby reducing the expense of the preparation of the fuel.

2. Economy in the consumption of fuel since carbonic acid produces when burning 8080 calories, whilst carbon monoxide produces only 247 3 calories.

fTllie process forming the subject-matter 0 t in subjecting the ore, mixed with the quantity of coal necessary for its reduction and towhich are added suitable fluxes, 'to the action of a flame obtained by the combustion of pulverized coal in the necessary quantity of superheated air in order that the combustion produces carbon monoxide and a cer-' tain quantity of carbonic acid less than that of carbon monoxide, in such a manner that e present invention consists therefore the oxidizing action exerted by this carbonic acid on iron during the reduction and melting does not reach a prejudicious proportion.

- Thus, for instance, if the combustion of the pulverized coal in the superheated air is earned out so as to give, no longer solely carbon monoxide, but 85% of carbon monoxide and 15% of carbonic acid, the reduction of the ore in this case, instead of being totalwill amount to 95%, but the loss of tain cases to lose a small fraction 0 reduced metal owing to the economy obtained by the diminution of the quantity of pulverized coal employed and of the greater facility of crushing the latter. p

The present process of reduction can be used in the processes described in my rior United States Patents Nos. 1,360,711, 1,372,-

pendmg- United might be therefore to advanta e in cer- States patent a a ilication filed onthe March superheated air, in order that the combuslOth, 1920, under Serial No. 364,704. tion produces carbon monoxide and a'smail Claim: quantity of carbonic acid in a proportion A process for the reduction of ores and smaller than that of carbon monoxide.

5 particularly iron ores, which consists in sub- The foregoing specification of my Procjecting the ore, mixed, with the quantity of ess for the direct reduction of ores, and parcoal necessary for its reduction and to which ticularly or iron ores, signed by me this are added suitable fluxes, to the action of 2nd day of vliebruary, 1923.

a flame obtained by the combustion of pul- 10 yerized coal in the necessary quantity of LUGIEN PAUL BASSET. 

